Grinding wheel dressing apparatus



Aug. 16, 1955 Filed May 4, 1953 Fig.1

N. HOGLUND GRINDING WHEEL DRESSING APPARATUS 6 Sheets-Sheet 1 INVENTOR Nils Hoglurzd ATTO Y Aug. 16, 1955 N. HOGLUND 2,715,397

GRINDING WHEEL DRESSING APPARATUS Filed May 4, 1955 6 Sheets-Sheet 2 fig. 2

lNVENTOR JVl'ls Ho ilund Aug. 16, 1955 HQGLUND 2,715,397

GRINDING WHEEL DRESSING APPARATUS Filed May 4, 1953 6 Sheets-Sheet 3 INVENTOR Nils Hoglund ATT NEY Aug. 16, 1955 N. HOGLUND 2,715,397

GRINDING WHEEL DRESSING APPARATUS Filed May 4, 1953 6 Sheets-Sheet 4 INVENTOR Nils Hoglund Aug. 16, 1955 N. HOGLUND 2,715,397

GRINDING WHEEL. DRESSING APPARATUS Filed May 4, 1953 6 Sheets-Sheet 5 A \x\\ S 19 4 5 0 3o F1 g. 6 3

INVENTOR N: Is Ho llund ATTO EY 6 Sheets-Sheet 6 N. HOGLUND GRINDING WHEEL DRESSING APPARATUS Aug. 16, 1955 Filed May 4, 1953 United States Patent 0 GRINDING WHEEL DRESSING APPARATUS Nils Hoglund, Summit, N. 3.

Application May 4, 1953, Serial No. 352,833

14 Claims. (Cl. 12511) to move the grinding wheel axially to and from its dressing position. Therefore it must be possible to rotate the dressing apparatus out of contact with the grinding wheel but at the same time put it quickly and accurately into, dressing position. This requires an apparatus having a rotatable support and retracting mechanism and which must be capable of being positioned within the small space available and which can also be quickly and accurately positioned for grinding operations. In this type of dressing operation steep profiles must be dressed which require a ratio mechanism which permits the use of a distorted template on which the template follower can climb and still give the proper predetermined movement to the dressing tool. This is accomplished with a template with a contour of the predetermined form to be dressed magnified several times in the axis parallel to the grinder spindle, but only one time in the axis perpen dicular to the grinder spindle. Thus in a four-to-one ratio arrangement, a three inch grinding wheel requires a twelve inch long template.

It is, therefore, an object of my invention to provide an improved grinding wheel dressing device or apparatus suitable for use with grinding wheels designed for grinding internal surfaces.

Another object of my invention is to provide such apparatus which can be positioned within a small space and which can be supported so as to be readily retracted from dressing position and be movable quickly into and out of dressing position and in which the retracting mechanism is simple and effective in its retracting operation.

A further object of my invention is to provide such apparatus in which retraction can be had quickly and yet in which the support and dressing tool can be accurately returned to dressing position with substantially no deviation from predetermined limits in the dressing position.

A still further object of my invention is to provide dressing apparatus of small dimensions which nevertheless gives any desired ratio relationship between the template and dressing tool and insures precision of the contour to be dressed.

A further object of my invention is to provide such apparatus in which the desired movements of the template and dressing tool can be had while retaining compactness of parts of the apparatus.

Briefly, a grinding wheel dressing apparatus made in accordance with my invention comprises a base on which is pivotally mounted an L-shaped support in turn sup- Patented Aug. 16,1955

porting a transverse slide guide upon which is mounted a slide and an elongated housing mounted vertically on the support and movable parallel to the axis of the grinding wheel to be dressed, in this case a grinding wheel normally mounted on a horizontal axis. The housing is provided with an extension supporting a dressing tool movable normally of the movement of the housing, that is, radially of the grinding wheel being dressed. Mounted within the housing is a slide movable parallel to the length of the housing and operated by fluid pressure operated means. On one surface is mounted a contour cam or template which is contacted by a tool slide. A ratio cam is mounted on its opposite surface and positioned in a plane normal to the plane of the contour cam. A fixed cam follower mounted on the pivoted L-shaped support extends Within the housing and engages the ratio cam. As the fluid operated means is placed in operation it causes the slide within the housing to move up and down in a vertical direction, causing movement of the housing parallel to the base and axis of the wheel being dressed and simultaneous movement of the tool which also moves parallel to the base but normal to the movement of the housing so that the dressing tool is carried across the surface of the wheel being dressed as it dresses the contour on the grinding wheel.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims, but the invention itself will best be understood by reference to the following description taken in connection with the accompanying drawing in which Figure 1 shows a front perspective view of a grinding wheel apparatus made according to my invention, Figure 2 shows a rear perspective of Figure 1, Figure 3 is an end view perspective with the housing cover removed to show details of construction, Figure 4 is a side elevation with parts broken away to show details of construction of the apparatus shown in Figures 1 and 2, Figure 5 is a transverse section taken along line 55 of Figure 4, Figure 6 is a transverse section taken along line -i6 of Figure 4, Figure 7 is a section taken along the line 7 of Fig. 5 with parts broken away to show details of the ratio cam and cam follower for causing movement of the housing, and Figure 8 is a section taken along line 38 of Figure 5.

General description Referring to Figures 1 and 2 of the drawings, a grinding wheel dressing apparatus made according to my invention includes a base 10 provided with a pair of upwardly extending arms or supports 11 and 12 having a pin or shaft 13 supported at the upper ends thereof. Pivotably or rotatably mounted on pin 13 is an L-shaped supporting structure 14, the shorter leg 15 of which extends more or less parallel to the base and has its free end fixed to the shaft 13. At the rear, a longer L-shaped portion 16 has a transversely extending slide supporting member 17 slidably supporting for transverse movement of portion 16 and parallel to the base an elongated vertically extending housing 18 provided with and mounted on the slide member 39, the slide member 19 and the housing 18 being secured together and movable as a unit. The housing supports thereon a tool support 2 3 also movable parallel to the base and normally of the housing movement as the tool travels along the surface of the grinding wheel being dressed in response to a contour cam as will be described. In order to be able to move the dressing tool into and out of contact with the grinding wheel to be dressed I provide a fluid operated or hydraulic cylinder 21 connected to supporting member 14 by a link 87 and piston rod 88. Normally, in dressing 7 position, the .L-shaped member and housing rest on the stop member 22,.

Means are provided within the housing 18 including a slide supporting cam and fluid operated mechanism connected thereto to cause movement of the housing parallel t the ase nd wheel b in esssd and a rad a mo m n f th r s in teal and s pppr 20-, As h h u ns moves x ally and Pa a lel to t e wheel, th l moves n a ou n accordance wi h a t mpla e o he slide to p dh the P oper which: n the gri ding eel- Cam and template slide As shown in Figures 3, 4, 5 7 there is mounted within e o n 1 a cam li h 3 hic games the contour cam or template 31 for controlling movement of the tool slide and support 20, and carries the ratio cam 32 n t othe o bac s de of he slide wh ch li s in t P n P p n icular t th p a o he co I cam and which controls the movement of the housing 18. The slide 30. is mounted by means of ball bearing assemblies 33 and 34 in guide supports 35 and 36 which are mounted within the housing 18.

Means Q in t e lide a o the ngit dina a i of the housing or back and forth in a vertical position n s a cy inder .3 on i i g a flui o e te P swh having piston rod 3.8 connected .to slide 30 by rigid connector 39. Th? fl lid operated piston is controlled by fluid under pressure, which is introduced into and ejected from the piston by means of the tubes 40 and 41.

Housing support and control Referring now to Figures 4, 5, 6 and 8, it will be seen that the pivoted L-support has supported at its upper end a slide guide and support 45 seeured to the slide supporting member 17 on leg 16 and on which is slidably supported slide 19 by means of ball bearing assemblies 47 and 48, the slide 19 being spring loaded by means of springs 50 and 51 contacting at one end extensions 52 and 53 on the slide 19. These springs are supported on spring guides and support members 54 and 55. The other ends of the springs butt against the Web or partition 56 of the slide guide 17. These springs urge the slide 19 and the supported housing 13 thereon to the left as viewed in Figures 1, 5, 6 and 7. Mounted on the slide support 17 is a bracket 60 to which is secured the cam follower 61. Follower 61 extends into the housing 18 and contacts the inclined surface of the elongated triangular? shaped ratio c m 32- i of cou se, obv qus that th cam 32 can be changed and can be given diiferent contacting surfaces lying at different angles to the vertical to change the ratio movement of the housing with respect to the vertical movement of the cam.

As .the slide 30 moves toward the base, inasmuch as follower -61 is-fixed, the housing 18 and slide 19 will be forced to the right as shown in Figure 7 against the action of the springs'50 and 51 -to.carry the tool across the sur-* face of the grinding wheel 75 as shown in Figure '5.

' When-the slide 30 moves upwardly the springs under compression move the slide and housing 19 to the left as shown in Figures and 7.

Tool slide Referring now to Figures 3, 4, 5 and '8, the housing 18 is provided with a lateral extension 70 in whichis mounted the tool slide 71, the slide'being mounted and supported in .ball bearing assemblies 72 and '73 and carryingrthe diamond tool 7.4 which forms the contour on grinding wheel '75. The slide also carries a dust cover 76. At the inner end of slide 71 is cam follower 77 which contacts the surface of the contour cam or template 31. The slide -71 .is spring loaded by means .of spring {78 :butting a transverse extension 70' of the portion's70 .:of the housing and contacting an extension 79 on slide .71 forvurgingthe slide and follower against the template 31.

Thus as the slide 30 and template '31 move up and down the toolslide 71 and tool 74 are made to move radially with respect to the wheel being dressed. The movement of the tool will correspond to the contour on the template, the contour dressed of course being a reduction of that on the template in a ratio corresponding to and controlled by the ratio cam 32. That is, movements of the housing and tool are matched to the width of the wheel being dressed and the depth of the contour to be dressed.

Retractor As best shown in Figure 4, the L-shaped supporting member 14 is provided with stop screw which can be adjusted to determine the dressing position of the apparatus. This permits delicate and accurate adjustment of the position of the dresser so that it returns exactly to the same dressing position at each dressing operation. The screw is provided with a boot or dust cover 86 to insure that no dust collects on the surface of the stop stud or member 32 to cause error in positioning to the dressing position.

Because the L-shaped support is used, and because of the position of the pivot at 13 relative to the position of tool 74-a small movement of the support 14 will cause a larger movement of the tool than if the pivot were in line with the tool. Also, since the center of gravity of the assembly is between the pivot '13 and the wheel being dressed, gravity alone is sufiicient to provide the force for maintaining the toolin Icontact with the surface being dressed until the stop member 22 is engaged by stop screw 85 which determines the limit of the movement of the tool '74, thus insuring that the tool-will always end its dressing. operations at an accurately determined position.

When it is desired -.to dress a wheel the apparatus is in the position shown in Figure 4. It is of course rotated out of position when desired by means of cylinder 21 and piston 88. 1

Properly controlled fluid pressure operated means al-' ternately causes :fluid to flow under pressure into and out of the tubes 40 .and 41 connected to the cylinder 37 in a functional manner not shown, causing a reciprocating motion of slide 30 in a vertical direction or in a direction normal to .the :base of the dressing apparatus and which is transverse of the axis of-the wheel being dressed. As described above, as the slide 30 moves up and down the cam 32 is also-moved up and down and because it is in 'contactwith =the fixed cam follower 61 the slide 19 and housing 18 are -caused to move parallel to the axis of the-wheel being dressed or in a horizontal plane and transversely of the -L-shaped support 14. At same time the .cam follower 7 7 of the tool slide 71, which is contact with-the contour cam or template 31, moves transversely of the movement of slide 30 and the housing 18.or radially of the wheel being 'dressedto grind the' contour corresponding to the contour of the The tool slide-71 and .contour cam 31 move in parallel planes but perpendicularly to each other.

Apparatus made according to my invention have all the advantages pointed out' above. That is, it is particularly suitable for dressinggrinding wheels designed for grinding internal surfaces. It can :be supported in cramped -spaees,- yet can-bereadil-y retracted from dressing position but accurately and quickly returned to dressing position. It -is simple in construction, -yet can dress steep contours accurately. It-is also compact without being .madecomplicatedl It is -easy to operatqrequiring no skilled labor, and easy :to adjust .for different ratios and contour shapes. a

.I .claim:

1..A grinding wheel dressing apparatus including .a base, a supporting memberpivoted on said base and means for moving said supporting member from a-prcdetermined dressing position to-another .position, a slide guide fixedto :saidsupporting. member, a housing mounted onsaid slide guide formovementtransversely-of said 5 supporting member, a first slide mounted within and movable transversely of the movement of said housing, a first cam mounted on said first slide and lying in one plane, a second cam mounted on said first slide and lying in a plane perpendicular to said one plane, a tool slide and follower slidably supported by said housing and movable normally to the movement of said first slide, said follower contacting one of said cams, a fixed follower secured to said supporting member and extending within said housing and contacting the other cam.

2. A grinding wheel dressing apparatus including a base, a supporting member pivoted on said base and means for moving said supporting member from a predetermined dressing position to another position, a first slide mounted on said supporting member for movement transversely of said supporting member and parallel to said base, a second slide mounted on and movable normally to the movement of said first slide, a first cam mounted on said second slide and lying in one plane, a second cam mounted on said second slide and lying in a plane perpendicular to said one plane, a tool slide and follower slidably supported by said first slide and movable normally to movement of said second slide, said follower contacting one of said cams, a fixed follower secured to said supporting member and contacting the other cam for causing movement of said first slide when said apparatus is placed in operation.

3. A grinding wheel dressing apparatus including a base, a supporting member pivoted on said base, means for moving said supporting member from a predetermined dressing position to a non-dressing position, a slide guide on said supporting member, an elongated housing having a slide and mounted on said slide guide for movement transversely of said supporting member, a first slide mounted within and movable longitudinally of said housing, a template mounted on said first slide and lying in one plane, a cam mounted on said first slide and lying in a plane perpendicular to said one plane, a tool slide and follower slidably supported by said housing and movable normally to said first slide and in a plane parallel to the plane of said one plane, said follower contacting said template, a fixed follower secured to said supporting member and extending within said housing and contacting said cam.

4. A grinding wheel dressing apparatus including a base and a vertically extending supporting member on said base, a slide guide on said supporting member, a housing mounted on said supporting member for movement transversely of said supporting member and parallel to said base, a slide mounted within and movable in one direction in said housing, a first cam mounted on said slide and lying in one plane, a second cam mounted on said slide and lying in a plane perpendicular to said one plane, a tool slide and follower slidably supported by said housing and movable normally to the movement of said first slide, said follower contacting one of said earns, a fixed follower secured to said supporting member and extending within said housing and in contact with the other cam.

5. A wheel dressing apparatus including a base, an L-shaped supporting member pivotably mounted on said base at the free end of one of the legs of said supporting member, the other of said legs having a slide guide thereon and means for moving said L-shaped supporting member to and from a dressing position, a slide and a housing thereon mounted on said slide guide for movement transversely of said L-shaped supporting member, a tool slide mounted on said housing and having a cam follower and a first slide mounted within said housing for movement parallel to one of the legs of said supporting member, a contour cam mounted on said first slide and contacting said tool slide follower, and another cam mounted on said first slide, and a fixed cam follower mounted on said supporting member and in contact with said other cam, and means for moving said first slide and the cams mounted thereon for causing movement of said slide and housing transversely of said L-shaped supporting member and said tool slide normally of the movement of said first slide.

6. A wheel dressing apparatus including a base, an L-shaped supporting member pivotably mounted on said base at the free end of one of the legs of said supporting member, the other of said legs having a slide guide thereon and means for moving said L-shaped supporting member to and from a dressing position, a first slide mounted on said slide guide for movement transversely of said L-shaped member, a tool slide mounted on said first slide and having a cam follower, and a second slide mdunted on said first slide for movement parallel to one of the legs of said L-shaped supporting member, a contour cam mounted on said first slide and contacting said tool slide follower, and another cam mounted on said second slide, and a fixed cam follower mounted on said L-shaped supporting member and in contact with said other cam, and means for moving said second slide and the cams mounted thereon for causing movement of said first slide transversely of said L-shaped supporting member and said tool slide normally of the movement of the second slide.

7. A wheel dressing apparatus including a base, a supporting member mounted on said base and extending perpendicularly thereto, a slide guide on said supporting member, an elongated housing having a slide mounted on said slide guide for movement transversely of said supporting member, said housing extending perpendicularly of said base, a tool slide mounted on said housing and having a cam follower and a second slide mounted within said housing for movement longitudinally of said elongated housing, a contour cam mounted on said second slide and contacting said tool slide follower, and another cam mounted on said slide, and a fixed cam follower mounted on said supporting member and extending into said housing in contact with said other cam, and means for moving said second slide and the cams mounted thereon for causing movement of said housing transversely of said supporting support and said tool slide normally of the movement of said housing.

8 A grinding Wheel dressing apparatus including a base, an L-shaped supporting member having a short leg and a long leg, the free end of said short leg being pivotably mounted on said base, a stop member on said base, means on said L.shaped member contacting said stop member for determining one position of said L-shaped supporting member, a slide guide mounted on the long leg of said supporting member adjacent the free end thereof, and a slide mounted on said slide guide, an elongated housing mounted on said slide and extending parallel to the longer leg of said supporting member, a cam slide mounted within said housing and having opposite surfaces thereon, a contour cam mounted on one surface of said cam slide and a ratio cam mounted on the opposite surface of said cam slide and in a plane at right angles to the contour cam, a tool slide mounted in said housing and movable normally of the movement of said cam slide and said housing and having a cam follower contacting said contour cam, and a fixed cam follower mounted on the longer leg of said supporting member and extending within the housing and contacting said ratio cam, and means for moving said cam slide longitudinally of said housing for causing transverse movement of said housing parallel to the axis of a grinding wheel being dressed and said tool slide normally of said housing.

9. A grinding wheel apparatus including a base, an L-shaped supporting member having a short leg and a long leg, the free end of said short leg being pivotably mounted on said base, a stop member on said base, and adjustable means mounted at the junction of the legs of said L-shaped member for determining one position of said L-shaped member, a slide support mounted on and extending transversely of the long leg of said supporting member adjacent the free end thereof, and a first slide mounted, on said slide guide and movable transversely of the legs of said L-shaped supporting member, a cam slide mounted on said first slide and movable parallel to the longer leg of said supporting member, a contour cam mounted onsaid cam slide and a ratio cam mounted on said, cam slide, a tool slide mounted on said first slide and having a cam follower contacting said contour cam, and a fixed cam follower mounted on the longer leg of said supporting member and contacting said ratio cam, and means formoving said cam slide for causing movement of said first slide transversely of said longer leg and said tool slide normally of said cam slide.

10. A grinding wheel dressing, apparatus including a base, supporting means extending from said base, an Lshaped member having the free end of one of the legs of said member pivotably mounted on said supporting means, a stop member mounted on said base, an adjustable contacting member mounted. on said L-shaped member for contacting with said stop member and positioned at the juncture of the legs of said supporting member, and means for rotating said L-shaped member about its pivot, a slide guide mounted adjacent the free end of the other leg of the L-shaped supporting member, a slide and housing supported thereon mounted on said slide guide, said housing having a cam slide therein movable parallel to said other leg, a contour cam and ratio cam mounted on said slide within said housing and lying in planes perpendicular to each other, a tool slide supported on said housing and having a follower contacting said contour cam and a fixed follower mounted on the other leg of said L-shaped member and contacting said ratio cam and means for moving said cam slide within said housing.

11. A grinding wheel dressing apparatus including a base, supporting means extending from said base, an L-shaped member having the free end of one of the legs of said member pivotably mounted-on said supporting means, a, stop member mounted on said base, an adjustable contacting member mounted on said L-shaped member for contact with said stop member and positioned at the juncture of the legs of said supporting member, and means for. rotating said L-shaped member abouts its pivot, a slide guide mounted adjacent the free end of the other leg of the L-shaped supporting member, a slide and an elongated housing supported thereon mounted in said slide guide, said housing extending parallel to the other leg and having a cam slide therein movable parallel to said other leg, a contour cam and ratio cam mounted on said slide and lying in plane perpendicular to each other, a tool slide supported on said housing and movable normally of the movement of said cam slide and having a follower contacting said contour cam, and a fixed follower mounted. on said other leg of said L-shaped member and contacting said ratio cam and means for moving said cam slide within said housing to move said housing in one direction and said tool slide normally to the movement of said housing.

12. A grinding wheel dressing apparatus including a base, supporting elements extending from said base, an L-shaped supporting member having a short leg and a long leg, the free end of said short leg being pivotably mounted on said supporting elements, a stop member on said base spaced from said supporting elements and a contacting member on said L-shaped member contacting said stop member for determining one position of said L-shaped member, a slide support mounted on the long leg of said supporting member adjacent the free end and extending housing, a tool slide mounted in said extension and mov-.

able normally of the movement of said cam slide and said housing and having a cam follower contacting said contour cam, and a fixed cam follower mounted on the long leg of said supporting member and extending within the housing and contacting said ratio cam, and means for moving said cam slide longitudinally of said housing for causing movement of said housing in one direction and move-.

ment of said tool' slide normally to the movement of said housing.

13. A grinding wheel dressing apparatus including a base, a supporting member mounted on said base, a slide guide mounted on said supporting member, and a first slide mounted on said slide guide for movement in one direction, a cam slide mounted, on said first slide and having opposite surfaces thereon, a contour cam mounted on one surface of'sai'd cam slide and. a ratio cam mounted on the opposite surface of said cam slide and in a plane at right angles to the contour cam, a tool slide mounted on saidfirst slide and movable normally of the movement of said cam slide and having a cam follower contacting said contour cam, and a fixed camfollower mounted on said supporting member andcontacting said ratio cam, and means for moving said cam slide for causing movement of said first slide in one direction and said tool slide normallyof the movement of said first slide.

14. A grinding wheel dressing apparatus including a base, supporting means extending from said base, and an L-shaped member having the free end of one of the legs of said member, pivotally mounted on said supporting means, a stop member mounted on said" base, an adjustable contacting member mounted on said L-shaped member and contacting said stop member and positioned at the juncture of the legs of 'saidsupporting member, and means for rotating said L-shaped member about its pivot, a slide guide mounted adjacent the free end of the other leg of said L-shaped supporting member and extending transversely; thereof, a slide and housing supported thereon mounted in said slide guide, said housing having a cam slide within movable parallel to said one leg and having opposite parallel surfaces, a contour cam and ratio cam mounted on the opposite surfaces of said cam slide and lying in planes perpendicular-to each other, a tool slide supported on said housing and movable normally of the movement of saidhousing; and having a follower contacting said contour cam and a fixed follower mounted on said other leg of-sa-id L-shaped member and extending into said housing and contacting said ratio cam and means for moving said cams slide Within said housing for causing movement of said housing inone direction along said slide guide and said tool slide normally of the movement of said housing.

References Cited. in the file of thisv patent UNITED STATES PATENTS 

